The idea here is to unify code that cares about changes to window size.

It also uses requestAnimationFrame (or fallback) where possible to optimize for rendering something in response to change. You can of course deboune handler further, but you get a bit of sane built-in debounce out of the box.

Also, it uses "backbone style" events. So from an ampersand-view, or backbone-view you can listenTo this one shared state object from several view and know that it'll get automatically unbound when the view is destroyed.